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im currently building an audio visualizer , my intentions were to use the LM741 but i saw that the LM324 operates using a single power supply , i would like to know if the LM324 can be used as Bandpass filters.

thank you.

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    \$\begingroup\$ Why limit yourself to only these two parts? Any electronic component distributor will have thousands of different opamps. Just look for one that matches what you need (RIRO? low power? stability? etc) \$\endgroup\$ – Joren Vaes Apr 10 '18 at 9:10
  • \$\begingroup\$ my goal is to use an opamp for audio filtering any suggestions \$\endgroup\$ – vijay Apr 10 '18 at 9:22
  • \$\begingroup\$ On its own no, but with some other components, yes \$\endgroup\$ – Colin Apr 10 '18 at 9:37
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    \$\begingroup\$ I suggest that you search for opamp based audio filter circuits and see what is used there. Yes you can make an audio filter using the LM324 and some passive components. Could that make a high quality filter: nope. Any designer that is serious about audio quality will not use an LM324, the NE5532 is often a better choice. It needs a higher supply voltage though. If you do not care about audio quality, sure use the LM324. \$\endgroup\$ – Bimpelrekkie Apr 10 '18 at 10:21
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The "single supply" op-amp is not a real advantage in an audio filter application where you are going to need to handle AC signals, so you either have to have bipolar (+/-) supplies or bias the signal so it is somewhere near the middle of the supply, either with resistors or by creating an artificial ground with a rail splitter circuit.

The LM324 is not very good for audio applications because it's got horrible crossover distortion, visible even at 60Hz. You can force the output stage into class-A operation with a pullup resistor that is sufficiently low value but that means it won't be able to swing down quite to the negative rail anymore. The obsolescent 741 or the (more available) dual 4558 is much more suitable, but still not great.

For audio applications you want low distortion, fairly high GBW product, especially if you want to make a high Q filter, and reasonably low noise, depending on the signal level you are working with. The NE5532 Bimpelrekkie suggested in a comment is one popular choice, TI (nee Burr-Brown) has some excellent other options with performance suitable for professional audio. I have recently used the rather excellent LME49710, for example, but unless you are looking for such high performance, there are cheaper (and lower power) solutions.

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Yes, you can use it to make audio filters.

LM324 is readily available and performs quite better than 741.

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  • \$\begingroup\$ If you want to save space, you may want to check LM358. It is identical to 324 but has 2 opamps. \$\endgroup\$ – Abdullah Baig Apr 10 '18 at 9:40
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    \$\begingroup\$ How will two op-amps save space when the LM324 has 4? \$\endgroup\$ – Andy aka Apr 10 '18 at 9:45
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    \$\begingroup\$ If he needs 2 op amps, he doesn't need to use the whole LM324. He can just use a LM358, hence save space. \$\endgroup\$ – Abdullah Baig Apr 10 '18 at 10:07
  • \$\begingroup\$ In exactly what way(s) do you believe the LM324 or 358 performs "quite better" than a 741 or 4558 in an audio application? \$\endgroup\$ – Spehro Pefhany Apr 10 '18 at 12:37

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